The present invention relates to vending machines and in particular to a motorized lock assembly for such vending machines.
Vending machines, such as may automatically dispense products to consumers, may provide a cabinet for holding the products to be dispensed and money handling machinery. The cabinet is normally covered by a lockable door that may, for example, extend over the entire front face of the vending machine, and which may seal the interior of the cabinet from the environment, often by means of a large flexible gasket extending around the perimeter of the door.
The lock of the vending machine door must both hold the door securely and provide for compression of the gasket to fully close the door. A common lock suitable for this purpose provides a pop-out T-handle that may be rotated to compress the gasket by drawing the handle in along a threaded shaft, and then pressed into a recess where the T-handle is prevented from further rotation and retained by a lock cylinder. Examples of such a lock are shown in U.S. Pat. No. 3,550,412, issued Dec. 29, 1970.
The time required to compress the gasket using a T-handle system (and conversely, to release the door by uncompressing the gasket) increases the time and cost of routine service of the vending machine, for example, to replenish stock and collect money. For this reason, motorized locks have been developed that may be triggered by a radio signal to begin unlocking the vending machine as a service person prepares for restocking, and that may automatically compress the gasket and lock the vending machine when restocking is complete as the service person completes other tasks. U.S. Pat. No. 6,581,986 describes a radio-controlled, motorized lock for vending machines that employs a bayonet that enters a slot and rotates to hold itself within the slot and then to pull the door closed, much like a T-handle system.
Improved security and a more uniform compression of the door gasket could be obtained through multiple locks joining the door and the cabinet. A single radio signal could coordinate these multiple locks, however, current motorized designs are prohibitively expensive.